The Boston Marathon bombing

April 15, 2013

Charles Krupa/Associated Press

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Medical workers aid an injured man at the finish line of the 2013 Boston Marathon following an explosion in Boston, Monday, April 15, 2013. Two bombs exploded near the finish of the Boston Marathon on Monday, killing two people, injuring 22 others and sending authorities rushing to aid wounded spectators, race organizers and police said. (AP Photo/Charles Krupa)

Charles Krupa/Associated Press

59of92

Medical workers aid an injured man at the finish line of the 2013 Boston Marathon following an explosion in Boston, Monday, April 15, 2013. Two bombs exploded near the finish of the Boston Marathon on Monday, killing two people, injuring 22 others and sending authorities rushing to aid wounded spectators, race organizers and police said. (AP Photo/Charles Krupa)